1. Field of Invention
This invention relates to a robot system, and more particularly to such a system which can efficiently perform complex tasks, such as adjustment, testing and assembly of products, and which is capable of being expanded in number of functions, can perform concurrently a plurality of parallel operations and can effectively be controlled in real time all with efficiency and reliability.
2. Description of the Prior Art
FIGS. 1,2,3 describe a conventional robot system and variations thereon, comprising a computer 1, a keyboard 2 for development of programs, input/output equipment 3, such as a CRT, a manual operation device 4, and input/output terminals 5 for connection with peripheral devices. The output from computer 1 is applied to servo-controllers 6.sub.1 -6.sub.n (which are equal in number to the number of joints of the manipulator, for example) for control of a robot arm 7. For causing the robot to conduct highly skilled operations similar to movements of the human arm requires use of two robot arms, and directions for moving the arms in cooperation with or by processing signals from visual sensors such as TV cameras.
Since the system shown in FIG. 1 has computer 1 as a main part, computer 1 is responsible for undertaking such functions. However, to accurately move the robot arms requires mathematical operations which range in the area of about ten thousand times per second for the calculation of data conversion applied on a cartesian coordinate into angular data for movement of the joints. Thus, it is difficult to accurately move the two arms simultaneously or to perform image processing.
FIGS. 2 and 3 depict conventional system which attempt to improve the above discussed difficulty. The system shown in FIG. 2 comprises a computer 1a used exclusively for moving an arm 7 and an image processing system 1b for processing signals from a vision sensor 8. Computer 1a and image processing system 1b are connected via a general purpose communication line (RS 232 C, etc).
The system shown in FIG. 3 comprises main computer 1, robot processors 1a, 1b for moving arms 7 and image processors 1c, 1d for processing signals from visual sensors 8, all under control of main computer 1.
However, since these conventional robot systems have been developed on the basis of numerical control (NC) machine tools, it has been difficult to attain highly skilled cooperative functions. Also, it is difficult to adjust the systems for frequent changes of tasks and frequent changes of products being worked on.